| Don't scale images in the browser (avoidScalingImages) | The page has 11 images that are scaled more than 100 pixels. It would be better if those images are sent so the browser don't need to scale them. | 0 |
| Description: It's easy to scale images in the browser and make sure they look good in different devices, however that is bad for performance! Scaling images in the browser takes extra CPU time and will hurt performance on mobile. And the user will download extra kilobytes (sometimes megabytes) of data that could be avoided. Don't do that, make sure you create multiple version of the same image server-side and serve the appropriate one. |
| Offenders: https://cdn.sokolov.ru/upload/content/area/7036ceb3fa64ea6a33ee738249088224.jpg https://pmdn.sokolov.io/pics/BC/78/0CDB73CC7F106A07A2CD8F5C299A.jpg https://pmdn.sokolov.io/pics/38/9C/D016DFFE37C198934F70DE38CB4B.jpg https://pmdn.sokolov.io/pics/6D/7E/C2785E3685C5261B70041BC93ABE.jpg https://pmdn.sokolov.io/pics/50/A8/AF837F4EE2E33544032842F6F129.jpg https://pmdn.sokolov.io/pics/BB/0B/B1E2DD99A233A3EE0C40BBA1184A.jpg https://pmdn.sokolov.io/pics/35/2D/7C48F720AA4A3EA9B8ABDF16D129.jpg https://pmdn.sokolov.io/pics/54/E7/D4FE0530594706A1AF586E4C86FA.jpg https://pmdn.sokolov.io/pics/82/27/A27F05511AF261785146EEF45AD4.jpg https://pmdn.sokolov.io/pics/31/36/B683F4781306F5E56133C27BD0BD.jpg https://pmdn.sokolov.io/pics/CF/26/F76FC343E2F85EFC18F3AD8F870F.jpg |
| Have a fast first contentful paint (firstContentfulPaint) | First contentful paint can be improved (2.210 s). It is in the Google Web Vitals needs improvement range, slower than 1.8 seconds. | 50 |
| Description: The First Contentful Paint (FCP) metric measures the time from when the page starts loading to when any part of the page content is rendered on the screen. For this metric, "content" refers to text, images (including background images), <svg> elements, or non-white <canvas> elements. |
| Inline CSS for faster first render (inlineCss) | The page has both inline styles as well as it is requesting 14 CSS files inside of the head. Let's only inline CSS for really fast render. | 90 |
| Description: In the early days of the Internet, inlining CSS was one of the ugliest things you can do. That has changed if you want your page to start rendering fast for your user. Always inline the critical CSS when you use HTTP/1 and HTTP/2 (avoid doing CSS requests that block rendering) and lazy load and cache the rest of the CSS. It is a little more complicated when using HTTP/2. Does your server support HTTP push? Then maybe that can help. Do you have a lot of users on a slow connection and are serving large chunks of HTML? Then it could be better to use the inline technique, becasue some servers always prioritize HTML content over CSS so the user needs to download the HTML first, before the CSS is downloaded. |
| Offenders: https://static-catalog.sokolov.ru/_next/static/css/bd86d97493927ccb.css https://static-catalog.sokolov.ru/_next/static/css/01b32e6e62b0bb19.css https://static-catalog.sokolov.ru/_next/static/css/bd6ac51bf6693b84.css https://static-catalog.sokolov.ru/_next/static/css/96498a5edb3ec413.css https://static-catalog.sokolov.ru/_next/static/css/923538a4e5a3c925.css https://static-catalog.sokolov.ru/_next/static/css/e66587858fbf2f69.css https://static-catalog.sokolov.ru/_next/static/css/2afb156d54a6ce9d.css https://static-catalog.sokolov.ru/_next/static/css/d0398fd163209f86.css https://static-catalog.sokolov.ru/_next/static/css/208cdcf6d3b30055.css https://static-catalog.sokolov.ru/_next/static/css/81423ca13e9f3c40.css https://static-catalog.sokolov.ru/_next/static/css/18fb03e4b746a20c.css https://static-catalog.sokolov.ru/_next/static/css/5bd6dffa208389a0.css https://static-catalog.sokolov.ru/_next/static/css/d32410ee3fa1a458.css https://static-catalog.sokolov.ru/_next/static/css/836fffc9a4348e28.css |
| Have a fast largest contentful paint (largestContentfulPaint) | Largest contentful paint is poor 10.012 s. It is in the Google Web Vitals poor range, slower than 4.5 seconds. | 0 |
| Description: Largest contentful paint is one of Google Web Vitals and reports the render time of the largest image or text block visible within the viewport, relative to when the page first started loading. To be fast according to Google, it needs to render before 2.5 seconds and results over 4 seconds is poor performance. |
| Offenders: https://pmdn.sokolov.io/pics/BC/78/0CDB73CC7F106A07A2CD8F5C299A.jpg |
| Avoid CPU Long Tasks (longTasks) | The page has 8 CPU long tasks with the total of 986 ms. The total blocking time is 586 ms . However the CPU Long Task is depending on the computer/phones actual CPU speed, so you should measure this on the same type of the device that your user is using. Use Geckoprofiler for Firefox or Chromes tracelog to debug your long tasks. | 0 |
| Description: Long CPU tasks locks the thread. To the user this is commonly visible as a "locked up" page where the browser is unable to respond to user input; this is a major source of bad user experience on the web today. However the CPU Long Task is depending on the computer/phones actual CPU speed, so you should measure this on the same type of the device that your user is using. To debug you should use the Chrome timeline log and drag/drop it into devtools or use Firefox Geckoprofiler. |
| Offenders: selfselfselfselfselfselfselfself |
| Avoid Frontend single point of failures (spof) | The page has 14 requests inside of the head that can cause a SPOF (single point of failure). Load them asynchronously or move them outside of the document head. | 90 |
| Description: A page can be stopped from loading in the browser if a single JavaScript, CSS, and in some cases a font, couldn't be fetched or is loading really slowly (the white screen of death). That is a scenario you really want to avoid. Never load 3rd-party components synchronously inside of the head tag. |
| Offenders: https://static-catalog.sokolov.ru/_next/static/css/bd86d97493927ccb.css https://static-catalog.sokolov.ru/_next/static/css/01b32e6e62b0bb19.css https://static-catalog.sokolov.ru/_next/static/css/bd6ac51bf6693b84.css https://static-catalog.sokolov.ru/_next/static/css/96498a5edb3ec413.css https://static-catalog.sokolov.ru/_next/static/css/923538a4e5a3c925.css https://static-catalog.sokolov.ru/_next/static/css/e66587858fbf2f69.css https://static-catalog.sokolov.ru/_next/static/css/2afb156d54a6ce9d.css https://static-catalog.sokolov.ru/_next/static/css/d0398fd163209f86.css https://static-catalog.sokolov.ru/_next/static/css/208cdcf6d3b30055.css https://static-catalog.sokolov.ru/_next/static/css/81423ca13e9f3c40.css https://static-catalog.sokolov.ru/_next/static/css/18fb03e4b746a20c.css https://static-catalog.sokolov.ru/_next/static/css/5bd6dffa208389a0.css https://static-catalog.sokolov.ru/_next/static/css/d32410ee3fa1a458.css https://static-catalog.sokolov.ru/_next/static/css/836fffc9a4348e28.css |
| Avoid extra requests by setting cache headers (cacheHeaders) | The page has 31 requests that are missing a cache time. Configure a cache time so the browser doesn't need to download them every time. It will save 296.4 kB the next access. | 0 |
| Description: The easiest way to make your page fast is to avoid doing requests to the server. Setting a cache header on your server response will tell the browser that it doesn't need to download the asset again during the configured cache time! Always try to set a cache time if the content doesn't change for every request. |
| Offenders: https://sokolov.ru/spa-images/footer/app-store-badge.svg https://sokolov.ru/spa-images/footer/google-play-badge.svg https://sokolov.ru/spa-images/footer/app-gallery-badge.svg https://sokolov.ru/spa-images/footer/rustore-badge.svg https://sokolov.ru/api/v5/profile/ https://sokolov.ru/api/v5/profile/products/ https://sokolov.ru/api/v5/handbooks/currency-rates/ https://sokolov.ru/api/v5/location/check/ https://sokolov.ru/api/v4/content/area/main-page-topline/ https://catalog.sokolov.ru/api/v2/filters/jewelry-catalog/rings/gold/ https://seo.sokolov.ru/api/v1/meta/ip/ https://sokolov.ru/api/v4/content/area/feedback-channels/ https://catalog.sokolov.ru/api/v2/catalog/jewelry-catalog/rings/gold/?per_page=72 https://sokolov.ru/api/v5/handbooks/delivery-info/ https://sokolov.ru/api/v5/products/sale-label/...ducts/sale-label/ https://sokolov.ru/api/v5/products/comment-info/...cts/comment-info/ https://sokolov.ru/api/v5/products/prices/.../products/prices/ https://pmdn.sokolov.io/pics/BC/78/0CDB73CC7F106A07A2CD8F5C299A.jpg https://pmdn.sokolov.io/pics/50/A8/AF837F4EE2E33544032842F6F129.jpg https://pmdn.sokolov.io/pics/38/9C/D016DFFE37C198934F70DE38CB4B.jpg https://pmdn.sokolov.io/pics/6D/7E/C2785E3685C5261B70041BC93ABE.jpg https://pmdn.sokolov.io/pics/BB/0B/B1E2DD99A233A3EE0C40BBA1184A.jpg https://pmdn.sokolov.io/pics/35/2D/7C48F720AA4A3EA9B8ABDF16D129.jpg https://pmdn.sokolov.io/pics/54/E7/D4FE0530594706A1AF586E4C86FA.jpg https://pmdn.sokolov.io/pics/82/27/A27F05511AF261785146EEF45AD4.jpg https://pmdn.sokolov.io/pics/31/36/B683F4781306F5E56133C27BD0BD.jpg https://pmdn.sokolov.io/pics/CF/26/F76FC343E2F85EFC18F3AD8F870F.jpg https://static-catalog.sokolov.ru/meta/manifest.json https://static-catalog.sokolov.ru/meta/favicon.ico https://tracking.diginetica.net/csc-event...ica.net/csc-event https://tracking.diginetica.net/csc-event...ica.net/csc-event |
| Long cache headers is good (cacheHeadersLong) | The page has 1 request that have a shorter cache time than 30 days (but still a cache time). | 99 |
| Description: Setting a cache header is good. Setting a long cache header (at least 30 days) is even better beacause then it will stay long in the browser cache. But what do you do if that asset change? Rename it and the browser will pick up the new version. |
| Offenders: https://cdn.diginetica.net/300/client-lite.js |
| Total CSS size shouldn't be too big (cssSize) | The total CSS transfer size is 78 kB and uncompressed size is 408.3 kB. That is big and the CSS could most probably be smaller. | 50 |
| Description: Delivering a massive amount of CSS to the browser is not the best thing you can do, because it means more work for the browser when parsing the CSS against the HTML and that makes the rendering slower. Try to send only the CSS that is used on that page. And make sure to remove CSS rules when they aren't used anymore. |
| Offenders: |
| The favicon should be small and cacheable (favicon) | The favicon has no cache time. | 50 |
| Description: It is easy to make the favicon big but please avoid doing that, because every browser will then perform an unnecessarily large download. And make sure the cache headers are set for a long time for the favicon. It is easy to miss since it's another content type. |
| Offenders: https://static-catalog.sokolov.ru/meta/favicon.ico |
| Avoid too many fonts (fewFonts) | The page has 4 font requests. Do you really need them? What value does the fonts give the user? | 60 |
| Description: How many fonts do you need on a page for the user to get the message? Fonts can slow down the rendering of content, try to avoid loading too many of them because worst case it can make the text invisible until they are loaded (FOIT—flash of invisible text), best case they will flicker the text content when they arrive. |
| Offenders: https://cdn.sokolov.ru/fonts/montserrat/bold.woff2 https://cdn.sokolov.ru/fonts/montserrat/regular.woff2 https://cdn.sokolov.ru/fonts/montserrat/medium.woff2 https://cdn.sokolov.ru/fonts/montserrat/semibold.woff2 |
| Avoid too many requests per domain [HTTP/1] (fewRequestsPerDomain) | The page has 1 domain that serves more than 30 requests. static-catalog.sokolov.ru got 71 requests. Improve performance by sharding those or move to HTTP/2. | 90 |
| Description: Browsers have a limit on how many concurrent requests they can do per domain when using HTTP/1. When you hit the limit, the browser will wait before it can download more assets on that domain. So avoid having too many requests per domain. |
| Offenders: static-catalog.sokolov.ru |
| Total JavaScript size shouldn't be too big (javascriptSize) | The total JavaScript transfer size is 600.9 kB and the uncompressed size is 1.8 MB. This is totally crazy! There is really room for improvement here. | 0 |
| Description: A lot of JavaScript often means you are downloading more than you need. How complex is the page and what can the user do on the page? Do you use multiple JavaScript frameworks? |
| Offenders: |
| Avoid using incorrect mime types (mimeTypes) | The page has 1 misconfigured mime type. | 99 |
| Description: It's not a great idea to let browsers guess content types (content sniffing), in some cases it can actually be a security risk. |
| Offenders: https://seo.sokolov.ru/api/v1/meta/ip/ |
| Make each CSS response small (optimalCssSize) | https://static-catalog.sokolov.ru/_next/static/css/bd86d97493927ccb.css size is 42.8 kB (42808) and that is bigger than the limit of 14.5 kB. Try to make the CSS files fit into 14.5 KB. | 90 |
| Description: Make CSS responses small to fit into the magic number TCP window size of 14.5 KB. The browser can then download the CSS faster and that will make the page start rendering earlier. |
| Offenders: |
| Don't use private headers on static content (privateAssets) | The page has 5 requests with private headers. The main page has a private header. It could be right in some cases where the user can be logged in and served specific content. But if your asset is static it should never be private. Make sure that the assets really should be private and only used by one user. Otherwise, make it cacheable for everyone. | 60 |
| Description: If you set private headers on content, that means that the content are specific for that user. Static content should be able to be cached and used by everyone. Avoid setting the cache header to private. |
| Offenders: https://sokolov.ru/jewelry-catalog/rings/gold/ https://catalog.sokolov.ru/api/v2/filters/jewelry-catalog/rings/gold/ https://catalog.sokolov.ru/api/v2/catalog/jewelry-catalog/rings/gold/?per_page=72 https://tracking.diginetica.net/csc-event...ica.net/csc-event https://tracking.diginetica.net/csc-event...ica.net/csc-event |
| Avoid missing and error requests (responseOk) | The page has 1 error response. The page has 1 response with code 404. | 90 |
| Description: Your page should never request assets that return a 400 or 500 error. These requests are never cached. If that happens something is broken. Please fix it. |
| Offenders: https://sokolov.ru/api/v5/profile/ |
0 s
2.5 sFirst Contentful Paint 2.465 sFirst Visual Change 2.467 s
3.5 s
4.4 s
5.4 s
6.8 sLayout Shift 0.00077 6.730 s
7.3 sLayout Shift 0.00826 7.239 sLayout Shift 0.00206 7.246 s
7.4 s
7.5 s
7.6 s
7.7 s
7.8 sLayout Shift 0.00004 7.714 s
7.9 sLayout Shift 0.00005 7.801 sLayout Shift 0.03046 7.852 s
8 sLayout Shift 0.00005 7.982 s
8.1 s
8.2 sCPU Long Task duration 228 ms
8.3 s
8.4 sLayout Shift 0.00028 8.336 s
8.5 s
8.6 sLayout Shift 0.00114 8.520 sCPU Long Task duration 53 ms
8.7 s
8.8 s
8.9 s
9 s
9.1 s
9.2 s
9.3 s
9.4 sCPU Long Task duration 172 ms
9.6 s
9.7 sLCP <> 9.659 s
10 s
10.1 s
15.8 s
15.9 s
16 s
16.1 sLast Visual Change 16.067 sVisual Complete 85% 16.067 sVisual Complete 95% 16.067 sVisual Complete 99% 16.067 s
